Pressure-tight grommet



J. DE SWART PRESSURE-TIGHT GROMMET Filed Dec.

Jan. 4, 1949.

Patented Jan. 4, 1949 -4 UNITED STATES PATENT OFFICE PRESSURE-TIGHTGROMMET Jan de Swart, Los Angeles, Calif.;assigx1o1,by"A mesne assignments, to Shellmar Products Corporation, Mount Vernon, Ohio, a corporation of Delaware I I I Application December 12, 1944,` Serial No.` 567,862 15 Claims. (Cl. 285-65) i I i 1 i i 2 My invention relates to pressure-tight of which are yieldableradially so that the retainer grommets, and among the objects of my invention element with its' skirt 4 maybe inserted through are: an opening in a partition or` the like and the First, to provide a grommet which is particutongues E spread so as to `bear against the marlarlysuited for manufacture from plastic. gins of the opening.

`Secondfto provide a grommet which is an The wedging element 2 is`likewise tubular in improvement of a conventional grommet, in that form and is providedy with a tapered or wedging provision is made to` effect a huid-tight seal end portion I` which isadapted to t through the around the cable or pipe threaded `through the opening in the partition P and slide between the grommet and the partition in which it is mounted. sleeve 3 and the skirt 4 to spread the tongues 6.

Third, to provide a grommet of this character The wedging element 2 is provided with an which incorporates a novel latching means to preexternal ilange'a which is adapted to bear against vent "separation of `the components of `the the partition P as the retainer and wedging elegrommet once they are assembled. ments `are telescoped, and thereby coact with the Fourth, to provide a grommet which may serve '15 extremities of the tongues 6 to clamp the partition also as a fastening means or hollow rivet for P.r The external flange 8 is preferably provided securing several plates together. with a ridge 9 directed toward the partition P, With the above and otherobjects in view as and an external packing ringv I0 is interposed may appear hereinafter, reference isdirected to between the partitionl"` and flange 8 to form a the accompanying drawings, in which: huid-tight seal. Fig. l is a side view of my pressure-tight The Ywedging element 2 is provided with a tubgrommet shown secured in a partition, the parular extension I I having a counterbore |24. The tition being shown fragmentarily. f retainer and wedging elements are adapted to Fig. 2 is an end view of the retainer element of receive a cable or conduit or other `cylindrical the grommet. Y member C. For convenience. this member will Fig. 3 is a side View thereof with one of` the be referred `to as a conduit, although it may, in

abutment tongues broken away to show the latchfact, be a single or multiple conductor cable or a ingslot. pipe for lluids.` A clearance space is formed be- Fig. 4 is an end view of the wedging sleeve ele- 4 tween 'the conduit C and the counterbore I2.

ment of the grommet. This space is adapted `to receive an internal Fig. 5 is a side View thereof and positioned-in packing ring I3. Thepacking ring I3 is normalalignment with Fig. 3 to illustrate the manner in 1y circular in cross-section and somewhat larger which the two elements are assembled. than the space between the counterbore and the Fig.` 6 is a longitudinal sectional view through cable, so that the walls of the packing ring are 6-6 of Fig. 1, showing ya cable in position within 35 compressed radially when the packing ring is the `grommet and showing one form of sealing forcedinto the counterbore around the conduit. means between the grommet and the cable. The packing ring is preferably formed `of rubber Fig. 7 is a fragmentary sectional view similar or so-called synthetic rubber and is sufficiently to Fig. 6, showing a modified form of sealing stretchable that itmaybe initially placed over means between the cableand grommet. the tubular extension II asindicatedby dotted Fig. 8 is an end view of the wedging element lines in Fig. 6. After the conduit has been posiand sealing means shown iny Fig. 7, with the cable tioned, the packing ring I3 is slipped from the omitted. tubular'ektensionto the second `dotted line posi- My invention comprises essentially a retainer tion shown in Fig. 6, and then forced into the element I and a wedging element 2, which are solid line position. While the packing ring may adapted to be tted through a hole in a partition be forced tightly against the shoulder forming P or other member, and caused to clamp the parthe inner end :of the counterbore I2, it is not tition around the margins of said opening. necessarythat thisbe done; instead, the packing The retainer element I includes a body element ring may occupy an intermediate position. and in the form of a sleeve or tubular member 3 of 50 be free to roll to a limited extent and permit uniform diameter. The sleeve 3 is provided with a nominal relative movement between the conduit frusto-conical skirt 4 which is secured to or and the grommet. i molded integrally with the sleeve at one end Thearrangementof the internal packing rmg thereof. The skirt 4 is provided with axially ex` described above is best suited for members havingv tending slots `.i forming tonguest the extremities metal surfacesg* or ati-least smooth, hard sur-- I faces. If the conduit is rubber covered or otherwise provided with a yieldable covering, an alternative form of packing may be employed as shown in Fig. '1. A packing collar I4 is slidable in the counterbore I2 preferably abutting the shoulder at the inner end of the counterbore and forming a .sea-l. The packing `collar I4 is lprovided with anvintern-al iiange I5 having an Aopening smaller than the conduit, so that it may press into the surface thereof and form a seal. The packing collar I4 is preferably split longitudinally, either axially as indicated at 16,01' vdiag-- onally so that it may be spread apart `ands/lipped over the conduit.

The various parts of my .grommet with the exception of the packing rings lli and I3 shown in Fig. 6, are preferably formed .of molded plastic. Such material affords an inherently high frictional contact between the wedging portion 1 and tongues 6 so that the retainer element and wedging element tend to maintain their positions when the parts of the .grommet are assembled in place. The packing collar .Il is likewise preferably formed of plastic, and in order to insure lcomplete sealing, a solvent may be applied to the confronting faces .of the slit I5.; in fact, to the entire surface of the packing -collar 4so that the slit is sealed and a bond formed between lthe packing collar and the tubular extension when the parts are assembled. y'.[t is also possible and feasible to apply the solvent to the wedging porton 'd immediately before insertion in the rustoconical skirt 4.

It is not always desirable, however, to apply a solvent between the retainer and wedging elements; instead, a latching means may be incorporated in these elements. For this purpose the sleeve 3 of the retainer element I, is provided with a longitudinally extending slot I1 located under one of the tongues 6, or if desired, within one .of the spaces between the tongues. The `slot I7 terminates in an undercut edge and the extremityr of the sleeve 3 in alignment with the slot I1 is provided with a beveled portion I8. 4The wedging portion 'I is provided with a pair of parallel slits I9 which form therebetween alatch tongue 2i! adapted to ride over the beveled portion vI8 and enter the slot ITI to latch with the undercut edge thereof. The latch may be provided with' a series of steps 2l so that the grommet may be secured to partitions of various thicknesses.

With either construction shown, my grommet affords a seal between the cable and partition which is notonly liquid-tight butair or gas-tight, and capable of maintaining its seal even though a substantial pressure differential exists between the sides of the partition.

Many other embodiments of the invention may be resorted to without departingfrom the `spirit. of the invention.

I claim:

1. A pressure-tight fgromm'et, comprising: an element having a plurality of expansible tongues.; a conduit; a tubular member adapted to expand said tongues and having an abutment flange adapted 'to co-act with said tongues to lsecure a plate therebetween; means adapted to secureV said element and said tubular member together; a sealing member interposed between said plate and flange; and -a sealing means interposed between said tubular member and conduit.

2. A pressure-tight grommet for insertion in an opening in a plate, comprising: -a pair rofrelatively yslidable telescoping tubular elements 4 adapted to receive aconduit; shoulder means on one of said elements and cooperating radially expansible means on the other of said tubular elements for clamping the opposite margins of the opening in the plate in which said tubular elements are inserted; means on said elements for .latchin'g them in vtelesccping relation; a first sealing .means lbetween onepf the tubular :elements and said plate; and a second sealing means between said tubular element and said conduit.

3. A pressure-tight grommet, comprising; a

tubular element adapted to be inserted through y ment coacting with said radially expansible portions to clamp said plate; a sealing member interposed fbetween said flange and plate; and a sealing means interposed between said tubular elem-ent and said conduit.

4. A Lconstruction as set -forth in claim 3, wherein said tubular element defines an internal cylindrical surface spaced from said conduit 'and said sealing .means is lin the form .of an of yie'ldable material radi-ally corn-pressed between usaid cylindrical vsurface and said conduit and in .rolling engagement therewith to .permit limited axial movement of said conduit relative to said tubular element.

5. .A `construction as lset kforth -in claim 3, wherein said sealing means `comprises a longitudinally vsplit collar tting within said tubular element and having .an Ainternal yflange adapted to press into the surface of `said conduit.

, 6. A fastening device comprising: a body element; a radially `flexible skirt attached to and overlying said body element; ya sleeve adapted to nt over .said body element and including a Wedging portion for radially spreading `said skirt, .and an yabutment shoulder adapted to coact Withsaid skirt to clamp Ya plate .through which :said sleeve extends; an axially hextending latch arm `formed in a wall ,of said sleeve.; .and means on said ybody engageable by said latch arm to interlock `said body element .and sleeve.

.7. A construction as set forth .in claim 6, wherein said latch arm is provided with a plurality of latch shoulders `sequentially engageable with said means as said sleeve is .moved onto said body element.

8. vA construction as ,set forth in claim 6, wherein said body element is tubular to receive a conduit; a sealing means is interposed between said sleeve and conduit and a .sealing member is interposed between said abutment and said plate.

9. A pressure 4tight grommet .adapted .to beV secured vin 4an opening in a plate., comprising: a pairV of Itelescoping tubular elements adapted to receive a conduit; one of said `tubular elements having a circumferential abutment.; expansible means on the `other of said tubular elements engageable by said abutment carrying tubular element and cooperating with said abutment lthereon for clamping l.the opposite margins of the opening in the .plate in which said tubular elements are to be secured; a latch means including an axially directed tongue on one of said elements and a vkeeper on the other of said elements for .relatively securing said elements in their clamping position; .means -for effecting a .seal

wherein said tubular element defines an internal cylindrical surface spaced from said conduit and said sealing means is in the form of an annulus of yieldable material radially `compressed between said cylindrical surface and said conduit and in rolling engagement therewith to permit limited axial movement of said conduit relative to said tubular element.

11. A construction as set forth in claim 9, wherein said sealing means comprises a longitudinally split collar tting within said tubular element and having an internal flange adapted to press into the surface of said conduit.

12. A pressure tight grommet as set forth in claim 1 wherein said tubular member is provided with an axially extending latch arm in the` wall thereof, and means on said first mentioned element engageable by said latch arm to interlock said first mentioned element and said tubuf expansible skirt to clamp the plate at the oppo` site margins of the opening in the plate, and cooperating interengaging latch means on said tubular elements for interlocking engagement.

14. A grommet as set forth in claim 13 wherein said latch engaging means comprises an axially extending latch arm on said outer tubular element, and means on said inner tubular element for interlocking engagement with said latch arm.

15. A grommet adapted to be secured in an opening in a plate, comprising an inner tubular element, a relatively stiff radially expansible skirt attached to said tubular element in overlying relation, a cooperating outer tubular element adapted to telescope said inner tubular element and expand said skirt, an abutment iiange on said outer tubular element cooperating with said expansible skirt to clamp the plate on the opposite margins of the opening therein, said inner tubular element being provided with an axially extending slot, and an axially extending latch arm on said outer tubular element having means for selective engagement in said slot to provide an adjustable interlocking connection between the tubular elements.

JAN DE SWART.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 207,871 Horton Sept. 10, 1878 i 785,106 Jones Mar. 21, 1905 1,063,926 Schuermann June 3, 1913 1,805,155 Weeks May l2, 1931 2,255,971 Hall Sept. 16, 1941 2,308,641 Brushaber Jan. 19, 1943 2,329,000 Rembort Sept. 7, 1943 

